BAGHDAD, Iraq (CNN) --After meeting with a top Shiite proponent of early elections, a U.N. envoy leading the study of Iraqi balloting indicated Thursday that many who favor a quick vote for a transitional legislature are having second thoughts after consulting with the U.N. electoral team.

"The people we have met are at least asking themselves questions, at the very, very least. I think they are looking for a consensus," said Lakhdar Brahimi, leader of the U.N. team.

Also, a consensus is emerging among many Iraqis for some sort of direct elections rather than the caucuses proposed by the United States, a U.N. diplomat in New York said.

The U.N. team visited Iraq during a violent week. On Thursday, the convoy of Gen. John Abizaid, commander of all U.S. forces in the Middle East, came under attack in the central Iraqi town of Fallujah from insurgents, who fired rocket-propelled grenades from rooftops. Abizaid and others in the convoy escaped injury. (Full story)

Hours later, an explosive device killed one U.S. soldier and wounded two others near Abu Gharib on the west edge of Baghdad.

On Tuesday and Wednesday, Iraqi security service recruits were targeted in two bombings and more than 100 were killed. Wednesday night, two U.S. soldiers died in roadside bombings.

The fragile security in many parts of the country has been cited as an obstacle to elections. Under heavy security, Brahimi traveled to Najaf Thursday and sat down with Grand Ayatollah Ali al-Sistani to discuss elections. Sistani is the driving force behind direct elections before the country's political handover by June 30 and an opponent of the U.S.-backed caucus plan.

After the meeting, sources reported signs the cleric and those who back him seem to be coming around to the view that staging direct elections before the country's political handover would be logistically unfeasible and unsafe. One source said opinion is emerging that would favor an election early in 2005.

Brahimi said he and Sistani agree that any elections should be properly organized but said the time frame is the issue.

"I think we are pointing out to them that perhaps the evaluations of the time that is needed, the conditions that need to be fulfilled, are not accurate, and they are listening to us," Brahimi said.

Cleric 'very likable' and 'extremely well-informed'

He and his team have interviewed a cross-section of people about elections and will meet with Secretary-General Kofi Annan on their findings. A report will be prepared with recommendations on how to proceed.

Elections rather than caucuses appear to be favored. In New York, U.N. spokesman Fred Eckhard said Annan understood a consensus was emerging from the team's contacts "that direct national elections are the best way to establish a parliament and government in Iraq that are fully representative and legitimate."

Musab al-Zarqawi, shown in an undated photo, is the most-wanted man in Iraq, coalition authorities say.

"I think they want support from the U.N.," said Brahimi, a longtime diplomat. "They think the U.N. has a role to play in helping them understand these problems and also in working out compromises and concerns amongst themselves."

In their meeting, about two-and-a-half hours long, Brahimi said Sistani -- whom he calls "very likable" and "extremely well-informed" -- stressed the need for full participation by all communities, including women.

Brahimi pointed out he wasn't negotiating an agreement with Sistani but trying to "understand what they want, point out to them what is obviously possible and not possible."

"I would be reluctant to speak on his behalf of what he has been convinced of or not, but I think we had a very, very good discussion," Brahimi said. "I listened to him very very carefully, and I hope -- I believe -- he also listened to me with attention. There was, I think, a rapport that [has] been established."

Brahimi said he would have visited more people during the trip if it weren't for security concerns.

"The Iraqi authorities, the [Coalition Provisional Authority] will really need to see how they can provide security for us if they want us to come back," Brahimi said. "It's useless to bring in large numbers of people if they are confined to bunkers."

Under the handover plan, agreed to by the U.S.-led Coalition Provisional Authority and the Iraq Governing Council in November, nationwide caucuses would choose a transitional national assembly by the end of May.

The assembly then would choose a transitional government, and the governing council and the coalition would transfer power to the new government by the end of June.

Coalition officials have said they support the principle of direct elections but that they would be logistically unfeasible this year.

After the transitional government takes power, the plan sets down three direct elections in 2005 -- a vote for delegates to a constitutional convention, a referendum on a constitution and elections for a new Iraqi government.

Coalition puts pressure on suspected terror leader

Meanwhile, coalition officials announced Thursday they had doubled the reward to $10 million for information leading to the capture of Musab al-Zarqawi, a Jordanian with links to al Qaeda who is accused of planning and executing numerous attacks.

Saying Zarqawi is the most-wanted man in Iraq, officials distributed a document they say he wrote to al Qaeda leadership in Afghanistan asking for more help and support.

Coalition Provisional Authority spokesman Dan Senor said the coalition wants all Iraqis to be familiar with Zarqawi's "action plan to tear this country apart" and turn it into an "ethnic bloodbath." (Full story)

"It is important for Iraqis to have a crystal clear understanding of this game plan so that when they are attacked, they are aware that it is not their fellow Iraqis attacking them," Senor said. "It is a foreign terrorist with ties to al Qaeda that is trying to turn this country upside down and promote bloodshed and tragedy."

U.S. officials said Zarqawi is suspected of improvised explosive device attacks as well as bombings last year at a mosque in Najaf and at U.N. headquarters in Baghdad.

He has been convicted in absentia in Jordan for his role in the October 2002 assassination of U.S. diplomat Laurence Foley and a December 1999 millennium plot to attack Western tourists.

Other developments

• An explosive device late Thursday killed one U.S. soldier and wounded two others near Abu Gharib on the west edge of the Iraqi capital, the Coalition Public Information Center said. According to CPIC, the attack occurred around 10:40 p.m. All three soldiers were members of the Army's 16th Military Police Brigade. Since the start of the war in March 2003, 540 U.S. troops have been killed -- 374 under hostile circumstances, 166 under non-hostile circumstances.

• German Chancellor Gerhard Schroeder on Thursday said his nation, which opposed military intervention in Iraq, is ready "to make a contribution" to the reconstruction of Iraq and "strongly help" move along the democratization process. "It does not make sense whatsoever to dig into historic reasonings about who wanted or didn't want what when it came to Iraq. That is all a past argument," Schroeder said during a news conference with British Prime Minister Tony Blair.

• The CIA has posted a notice on its Web site offering rewards for information that helps in the search for weapons of mass destruction in Iraq. A spokesman for the agency told Reuters that "it's just trying to get the word as broadly publicized as possible."